A semiconductor chip is formed with a fine electronic circuit by high-density integration, and during a fabrication process, each electronic circuit undergoes a test on whether it operates normally or abnormally.
For the test on the semiconductor chip, a contact probe, which electrically connects a terminal of the semiconductor chip and a contact point (pad) of an inspection circuit board for applying a test signal, has been used for semiconductor inspection. In general, the semiconductor chip includes terminals arranged having a very fine pattern. Thus, to perform the inspection by contact with the terminals having the very fine pattern, the contact probe needs to have a very fine size to be integrated and supported on a probe supporter.
Further, to minimize loss caused in the test of the test socket for inspecting the semiconductor chip particular about properties, the contact probe needs to have a short length to make a short signal path. However, if the contact probe has the short length, it is difficult to give the contact probe the elasticity enough to absorb pressure applied for the test.
To solve such problems, Korean Patent No. 10-1193556 has disclosed that a printed circuit board mounted with electronic parts and a test socket are integrated. Such a conventional test socket has a structure that a plurality of through holes are arranged in a printed circuit board, and an inner wall of each through hole is coated with a conductive film, and a contact probe (i.e. a conductive rubber) is placed in the through hole and connected to an electric part of the printed circuit board.
However, the conventional test socket is difficult to be used for inspecting a subject having a fine pitch since it has a structure that the contact probe (i.e. a conductive rubber), the electronic parts and a conductive path are formed in a single substrate.
Further, it is very complicated to design the test socket, and thus a production cost increases.